The Permanent Service for Mean Sea Level is a repository for

tide gauge A tide gauge is a device for measuring the change in sea level relative to a vertical datum. It its also known as mareograph, marigraph, sea-level recorder and limnimeter. When applied to freshwater continental water bodies, the instrument may ...

data used in the measurement of long-term

sea level change Globally, sea levels are rising due to human-caused climate change. Between 1901 and 2018, the globally averaged sea level rose by , or 1–2 mm per year on average.IPCC, 2019Summary for Policymakers InIPCC Special Report on the Ocean and Cryo ...

. The PSMSL is based at the

National Oceanography Centre The National Oceanography Centre (NOC) is a marine science research and technology institution based on two sites in Southampton and Liverpool, United Kingdom. It is the UK’s largest institution for integrated sea level science, coastal and d ...

Liverpool Liverpool is a city and metropolitan borough in Merseyside, England. With a population of in 2019, it is the 10th largest English district by population and its metropolitan area is the fifth largest in the United Kingdom, with a popul ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. It was founded in 1933 as the

IUGG The International Union of Geodesy and Geophysics (IUGG; french: Union géodésique et géophysique internationale, UGGI) is an international non-governmental organization dedicated to the scientific study of Earth and its space environment usi ...

Mean Sea Level Committee, and adopted as a Permanent Service of the

International Council for Science The International Council for Science (ICSU, after its former name, International Council of Scientific Unions) was an international non-governmental organization devoted to international cooperation in the advancement of science. Its members ...

(ICSU) in 1958. The tide gauge data are freely accessible by all, and consist predominantly of monthly-mean and annual-mean sea levels. The primary,"Revised Local Reference" data set has a continuous history of benchmark surveys for each gauge, ensuring that sea level is measured relative to a known land-based datum. There is also a "Metric" data set without such datum control, and a set of hourly and daily ocean bottom pressure data from the open ocean. The latter has no datum control, and the instruments are prone to calibration drift, so the bottom pressure data are useful only for oscillations with periods significantly shorter than the length of an individual instrument deployment (typically 1 year). The PSMSL is financially supported by the UK

Natural Environment Research Council The Natural Environment Research Council (NERC) is a British research council that supports research, training and knowledge transfer activities in the environmental sciences. History NERC began in 1965 when several environmental (mainly geogr ...

, the

World Data System In its most general sense, the term "world" refers to the totality of entities, to the whole of reality or to everything that is. The nature of the world has been conceptualized differently in different fields. Some conceptions see the worl ...

, and the

Intergovernmental Oceanographic Commission The Intergovernmental Oceanographic Commission of UNESCO (IOC/UNESCO) was established by resolution 2.31 adopted by the General Conference of UNESCO. It first met in Paris at Unesco Headquarters from 19 to 27 October 1961. Initially, 40 States becam ...

References

External links

* Natural Environment Research Council Research institutes in Merseyside Sea level {{int-org-stub